Articles of commerce are often tagged with an electronic article surveillance, EAS, tag that can be detected by an antenna system that is situated at an exit of a store that sells the articles of commerce. When an article having an EAS tag that has not been deactivated passes a security checkpoint, an alarm is generated. In order to prevent setting off the alarm, a tag of a purchased article is deactivated at a point of sale. In one type of tag, deactivation is accomplished by exposing the tag to a high frequency, UHF, signal of an antenna that induces a voltage across a metal-oxide semiconductor, MOS, device that exceeds the breakdown voltage of the MOS device, thereby destroying the MOS device and achieving deactivation. For example, such a tag is described in U.S. Pat. No. 8,013,742, entitled “Metal Oxide Semiconductor Device for Use in UHF Electronic Article Surveillance System.” The typical breakdown voltage is around 5 volts and an E field at resonance of about 70 Volts/meter is required for breakdown to occur.
A disadvantage of some known deactivation antennas is the high far field emitted from these antennas which may interfere with surrounding electronic equipment and may violate regulatory emission rules, for example, those promulgated by the Federal Communication Commission, FCC. Also, some tags located behind a preferred zone near a deactivator may be inadvertently deactivated.